The defendant was a 14-year old girl of low intelligence who had started a fire in a shed. She had poured white spirit on the floor and set it alight. The magistrates applied the test laid down in R v Caldwell but inferred that in his reference to "an obvious risk" Lord Diplock had meant a risk which was obvious to the particular defendant. They acquitted the defendant because they found that the defendant had given no thought at the time to the possibility of there being a risk that the shed and contents would be destroyed, and this risk would not have been obvious to her or appreciated by her if she had thought about the matter. The prosecution appealed by way of case stated.

Held:

If the risk is one which would have been obvious to a reasonably prudent person, once it has also been proved that the particular defendant gave no thought to the possibility of there being such a risk, it is not a defence that because of limited intelligence or exhaustion she would not have appreciated the risk even if she had thought about it.